[SCTP] Fix incorrect setting of sk_bound_dev_if when binding/sending to a ipv6

link local address.

Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 15 insertions, 21 deletions

diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index c9d9ea064734..c7e42d125b9c 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -812,26 +812,23 @@ static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr)
         if (addr->sa.sa_family != AF_INET6)
                 af = sctp_get_af_specific(addr->sa.sa_family);
         else {
-                struct sock *sk;
                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
-                sk = sctp_opt2sk(opt);
+                struct net_device *dev;
+
                 if (type & IPV6_ADDR_LINKLOCAL) {
-                        /* Note: Behavior similar to af_inet6.c:
-                         *  1) Overrides previous bound_dev_if
-                         *  2) Destructive even if bind isn't successful.
-                         */
-
-                        if (addr->v6.sin6_scope_id)
-                                sk->sk_bound_dev_if = addr->v6.sin6_scope_id;
-                        if (!sk->sk_bound_dev_if)
+                        if (!addr->v6.sin6_scope_id)
+                                return 0;
+                        dev = dev_get_by_index(addr->v6.sin6_scope_id);
+                        if (!dev)
                                 return 0;
+                        dev_put(dev);
                 }
                 af = opt->pf->af;
         }
         return af->available(addr, opt);
 }
 
-/* Verify that the provided sockaddr looks bindable.   Common verification,
+/* Verify that the provided sockaddr looks sendable.   Common verification,
  * has already been taken care of.
  */
 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
@@ -842,19 +839,16 @@ static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr)
         if (addr->sa.sa_family != AF_INET6)
                 af = sctp_get_af_specific(addr->sa.sa_family);
         else {
-                struct sock *sk;
                 int type = ipv6_addr_type(&addr->v6.sin6_addr);
-                sk = sctp_opt2sk(opt);
+                struct net_device *dev;
+
                 if (type & IPV6_ADDR_LINKLOCAL) {
-                        /* Note: Behavior similar to af_inet6.c:
-                         *  1) Overrides previous bound_dev_if
-                         *  2) Destructive even if bind isn't successful.
-                         */
-
-                        if (addr->v6.sin6_scope_id)
-                                sk->sk_bound_dev_if = addr->v6.sin6_scope_id;
-                        if (!sk->sk_bound_dev_if)
+                        if (!addr->v6.sin6_scope_id)
+                                return 0;
+                        dev = dev_get_by_index(addr->v6.sin6_scope_id);
+                        if (!dev)
                                 return 0;
+                        dev_put(dev);
                 }
                 af = opt->pf->af;
         }